Genera Ferocactus and Echinocactus
English name: Most species are called barrel cactus
Spanish name: biznaga (a general name for barrel-shaped cacti)
Description
The following is a general description for both genera of barrel cacti: The stems are globular to columnar, usually unbranched, and pleated, ranging from less than a foot (30 cm) tall in the smallest species to 6 to 12 feet (1.8-3.7 m). The central spines are the larger of two types and arise from the center of the areole; the principle central spine often has a different shape from that of all the other spines. Radial spines are smaller and arise from the margins of the areoles. The short, funnel-shaped flowers are very stiff and usually don’t extend beyond the spiny armor. The thick rind of the fruit is moist in Ferocactus, dry at maturity in most Echinocactus. The seeds are packed in a dry interior, not embedded in pulp. Echinocactus differs from Ferocactus in having sharp-pointed scales on the flower tubes and woolly ovaries.
Range
There are 25 species of Ferocactus and 6 of Echinocactus in the world. In the Sonoran Desert there are 9 and 2 species, respectively.
Notes
The majority of Ferocactus species flower in summer and are pollinated by bees in the genus Lithurge. The fruit and seeds are eaten by rodents, birds, mule deer, bighorn sheep, and javelina. The plant itself is eaten by cactus beetles (Moneilema gigas and other species), jackrabbits, packrats, and javelina.
The surface area of barrels and other more or less globose plants is small compared to the volume, so evaporative losses are small relative to the large volume of water stored. Repeat photography of sites in Baja California in 1905 and the 1990s indicate that the life spans of barrel cacti are typically less than a century.
One of the great fables of desert survival is that barrels and other cacti are reservoirs of water that can be easily tapped and drunk. It is true that indigenous peoples and a few other desert residents know how to obtain emergency water from cacti. But most city dwellers, including most aspiring survivalists, could not get water from any cactus if their lives depended on it (pun intended).
The first problem is getting to the pulp inside the very tough and spiny epidermis. A pocket knife is inadequate, and tools that are typically carried in a car, such as tire irons, aren’t very effective either. The labor of cutting into a barrel on a hot day is likely to cause loss of more water from sweating (and perhaps bleeding) than one would gain from the cactus.
Secondly, the water in cactus pulp is tightly bound in a gooey mucilage. ost of the year the pulp is more like a damp sponge than a watermelon—you can’t squeeze much liquid out of it. Furthermore, the raw pulp of many cacti is inedible. Some species have potentially toxic levels of oxalic acid (prickly pears), bitter and sometimes toxic alkaloids (senita and many other cacti), or other substances that cause diarrhea (some barrels) or vomiting. The best cactus for emergency water is Ferocactus wislizeni. See more details under that species. For a historical account of extracting water from a barrel cactus (in cool weather and when it was legal), see Camp-Fires on Desert and Lava by William T. Hornaday, pages 216-219.
Water can be obtained from cacti using a machete and solar still. But anyone with the foresight to pack these tools is smart enough to carry plenty of water and inform friends of the itinerary and expected return date!
Caution: native wild cacti are protected by state laws; it is illegal to take or destroy them. In addition, most barrels cannot branch, so cutting out the top is lethal.
Echinocactus polycephalus
English names: many-headed barrel,cottontop cactus
Spanish name: biznaga de chilitos (little chile barrel)
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Description
This Echinocactus is unique as the only barrel in our region that branches under normal conditions. The 8-inch (20 cm) diameter heads occur in clusters of up to 200, forming mounds to 3 feet (1 m) across and somewhat less high. The dense, stout spines obscure the plant bodies and restrict the small yellow flowers from opening fully; they appear in July. The brown spines appear bright red when wet from rain.
Range
This cactus occurs mostly on rocky and gravelly slopes in the driest parts of the Sonoran and Mohave deserts. It is rarely found where rainfall exceeds 5 inches (130 mm). (E. polycephalus var. xeranthemoides, occurs in the northern Mohave and Great Basin deserts, where there is more rain.)
Notes
Many-headed barrel cacti are slow-growing and probably very long-lived. Plants grown from seed at the Desert Museum are just beginning to branch at nearly 20 years of age. This species is also geographically stable; its range has not changed for at least the past 30,000 years despite the dramatic climatic swing from ice age to a warm interglacial period. Though the fruits seem to be imprisoned within the spiny armor, birds and packrats can get to them and disperse the seeds.
Turk’s head or eagle’s claw cactus (E. horizonthalonius var. nicholii) is in the same genus but has a different growth habit; it nearly always has a single stem. One variety of Turk’s head is common and widespread in the Chihuahuan Desert. Our variety is endangered and restricted to 3 small populations in Arizona and Sonora on limestone. The flowers are pollinated by bees. The fruits remain buried among the spines; they eventually disintegrate and the seeds simply fall to the base of the mother plant. Bighorn sheep and javelina eat the whole plants and probably function as occasional long-distance seed dispersers. Javelina only recently migrated into the Sonoran Desert, and their added predation may be exterminating this cactus.
Ferocactus cylindraceus [F. acanthodes]
English names: spiny barrel, California fire barrel, compass barrel
Spanish name: biznaga
Description
This barrel cactus is narrow-columnar rather than barrel-shaped. It grows up to 10 feet (3 m) tall, but is usually less than half that. Stems are nearly always single; like most other barrels this cactus branches only when the tip is damaged. The spines are usually reddish (bright red when wet), but yellow or brownish in some forms. The central spines are flat and curved at the tips, but not hooked. The many bristly radial spines obscure the body of the plant. Crowns of flowers are crowded among the dense spines at the stem tips and are almost always yellow, though some plants in the Pinacate region have orange to red flowers. Flowering is usually in March and April; some populations near Phoenix flower in summer.
Range
The spiny barrel occurs in northern Baja California and Sonora, southern California, and Arizona. It usually grows on steep rocky slopes, rarely occurring side-by-side with the fishhook barrel, which generally is found on gravelly bajada soils.
Notes
Because of this barrel’s cylindrical shape, it could be confused with a young saguaro if one fails to notice the hooked spines. The Seri name for this species means “thinks it’s a saguaro.” In Baja California F. cylindraceus can be confused with F. gracilis; the latter species has red flowers while those of the former are almost always yellow.
Ferocactus emoryi [F. covillei]
English name: Coville barrel,
Emory’s barrel
Spanish name: biznaga
Description
The description that follows applies to the desert populations of this barrel. Coville barrel is easily recognized by the relatively few spines per areole, all of which are stout (not bristly). The main central spine in each areole, usually red, is strongly flattened and hooked. Young plants are first globular, then barrel-shaped, but more slender than fishhook barrels. They are typically 1 to 4 feet (30-120 cm) tall. The bright red flowers open in July to mid-August before F. wislizeni blooms. Juvenile plants are very distinctive in bearing their spines at the ends of large tubercles rather than along ribs; they look like giant mammillarias.
Range
This desert form occurs from south-central Arizona to central Sonora.
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Notes
The Seri name for this species translates “barrel that kills.” Eating its flesh or juice causes nausea, diarrhea, and temporary paralysis. The Seri use the pulp as a pain-relieving poultice, further evidence that there are some active chemicals in this plant. However, the flowers and fruit are edible (no cactus fruit is poisonous, though some are inedible).
The desert populations were originally described as F. covillei. The populations in the thornscrub of southern Sonora (the original F. emoryi) are massive barrel-shaped plants up to 9 feet (2.7 m) tall and almost 3 feet (0.9 m) in diameter, with shorter curved but not hooked yellow spines and yellow flowers. Between Hermosillo and Guaymas, Sonora, the 2 forms intergrade, which is why they were combined into a single species. It’s exciting to see the variability in such intergrading populations. We found one plant that had both red and yellow flowers; they opened yellow and changed color with age.
Ferocactus emoryi var. rectispinus
English name: straight-spined barrel
Spanish name: biznaga
Description
Plants are barrel-shaped when young and rarely exceed 3 feet (1 m) tall. They become more cylindrical in age and occasionally reach 9 feet (2.7 m). This barrel cactus is easily recognized by its 6- to 11-inch (15-28 cm) long, straight central spines. When backlit by the sun on a rocky slope, it is surrounded by a glowing reddish aura that is much larger than the plant’s body. It has a few stout radials, but lacks bristly spines. The yellow flowers bloom in August and September.
Range
This is a rare cactus that occurs in its pure form only near the gulf coast of central Baja California. A few miles inland it hybridizes freely with F. peninsulae, forming hybrid swarms with variable spine lengths and curvature, and red-tinted flowers.
Notes
Straight-spined barrel is one of the many outstanding botanical marvels of Baja California. Many cactophiles have ventured off the main highway to seek it and pay homage to it. Because populations are very sparse and the terrain extremely rugged, it is a difficult quest, and finding even a single specimen is a thrill.
Ferocactus wislizeni
English names: fishhook barrel, Arizona barrel, compass barrel
Spanish name: biznaga de agua
(water barrel)
Description
The thick, barrel-shaped body of this cactus is usually 2 to 4 feet (0.6-1.2 m) tall, occasionally reaching over 10 feet (3 m). The ribs bear broad, flat, strongly-hooked central spines as well as several bristly radial spines, but not enough of these to obscure the stem. The flowers are not strongly crowded by the spines and open wide. Flower color is extremely variable; on most plants they are some shade of orange, often with a stripe of darker shade on each petal. About 10percent of the plants have yellow or red flowers. They are produced over a 2-month-long season, August and September, much longer than the blooming period of other barrels.
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Range
Populations of this barrel are concentrated in south-central Arizona and adjacent northern Sonora. There are also some populations in southern New Mexico and western Texas. The distinct variety on Tiburón Island may well be a distinct species. The fishhook barrel is most abundant on gravelly bajadas; it is less common on rocky slopes or silty valley floors.
Notes
This is the barrel that the Seri and others prefer to use for emergency water; Seris have survived on it for as long as a month. The juice is flat-tasting but not completely harmless. Drinking it on an empty stomach often causes diarrhea, and some Seri experience pain in their bones if they walk a long distance after drinking the juice. The seeds are not enclosed in a juicy pulp, but are edible, as is the sour rind. The O’odham eat the persistent fruit much of the year as an emergency food. The Seri also eat the flowers and buds.
Cactus bees (Lithurge spp.) pollinate the flowers. The fruit persists until it is removed by animals and may remain on the plant for more than a year. Birds, squirrels, and large mammals such as deer and javelina are the main consumers of the fruit. Plants grow fairly slowly, and large specimens are more than a century old. In cultivation, with supplemental water and fertilizer, they reach flowering size of 10 inches (25 cm) diameter and the same in height in about 12 years.
Ferocactus wislizeni and F. cylindraceus have the vernacular name “compass barrel” because large plants of these species tend to lean toward the southwest. It has been hypothesized that the intense heat from the afternoon sun retards growth on the southwest side of the plants, and the greater growth on the cooler side pushes the plants over. Large leaning plants may topple when the soil is softened by heavy rains. Ferocactus herrerae (twisted barrel) is included in F. wislizeni by some botanists. As the common name suggests, its ribs are often spiraled. It is found in southern Sonora and into Sinaloa. Its flower color (always yellow with brown tips) and its distribution (there is a 100 kilometer gap in Sonora where neither barrel occurs) give rise to some doubt that it belongs to the same species as fishhook barrel.
